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All eyes on SWM onset

The much delayed onset of SWM is expected anytime over Kerala. It is expected to be a slow start for the monsoon and IMD forecast is not encouraging. Hope things change for the better and nature proves all forecasts wrong.

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A few days back on sun news , very sad part is the extreme unawareness in media side ..one can see Jayanthi mam getting frustrated by media guy’s irrelevant questions and views quite often ….The media guy has got into conclusions , that el nino would send hot air into India from Pacific thru bay of bengal , whereas on west coast , western ghats stops it ,,,,,,
“”VERY VERY PATHETIC SITUATION”” ……..

Instead of him interrupting several times there , chance should have been given for Jayanthi mam to explain some concepts in the beginning, so that everyone including viewers and the anchor would have come to know about the topic to some extent. Very bad that in our country still this advanced topic is being ill treated

Rain forecast, a gamble on monsoon
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If India’s monsoon forecast turns out to be accurate, the country will be facing its 12th worst drought since 1950 and two consecutive years of the calamity for only the fourth time and the first time in 30 years. However, a private weather service and the meteorological department’s own track record raise some questions on the forecast.

“You show me one model which is able to do a better job,” D.S. Pai, Chief Forecaster at the IMD, toldThe Hindu. There are a large number of unpredictable factors in the development of the monsoon and the longer range the forecast is, the greater the likelihood of error, he said. The IMD has been putting on trial a new supercomputer-driven model which has forecast an even more deficient monsoon, at 86 per cent with a five per cent error margin.

Mapping the monsoon, with all its complexities and the various factors that influence it, is a tough task at the best of times. For example, as meteorologist Eric Holthaus says, should the El Nino phenomenon die out more quickly, or if the Indian Ocean dipole strengthens, both would suggest more rain than is forecast.

Pre-monsoon Rain continues in Karnataka, ending 8.30 am on 03.06.2015
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The east-west shear zone roughly along Lat. 10° N persists and now extends between 3.1 & 4.5 kms a.s.l. The cyclonic circulation over Lakshadweep area and neighbourhood has become less marked. However a trough of low at mean sea level lies over Lakshadweep area and neighbourhood. It may organize into a low pressure area during next 48 hours.

Rains across Kerala, monsoon may hit state in 48 hours
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Thiruvananthapuram/Hyderabad/Shimla/Kolkata: Pre-monsoon rains brought down temperatures in some states while monsoon seemed set to hit Kerala within 48 hours, the India Meteorological Department (IMD) said on Wednesday.

The temperature in several parts of Kerala rose on Tuesday but on Wednesday evening, dark clouds formed at many places and by late night it showered in many places across the state.

An IMD official forecast rains across Kerala in the next 24 hours. Fishermen have been warned about winds blowing 45 to 55 km an hour on the coast.

Weather officials are analysing the data recorded at 14 weather stations located at the Lakshadweep, Kerala and Mangalore in Karnataka. The onset of monsoon is declared on the basis of amount of rain received at these 14 stations. Wind and cloud formations are other indicators.

tis arabian sea system must b related to wave activity.. enhanced divergence all around particularly twrds south east driving into s.hemishere, even west, and more importantly jet streams dipping from north into central arb sea as trough… action that are happening above 12km is getting reflected in surface!! mind blowing nature..attached earth null image and 200hpa divergence map

Very good news for water starved Chennai and other east coast cities. A fresh water river up to the width of 100km flows in BOB from North to Kanyakumari for 2.5 months. In future this could harvested and stored .

SWM Onset over Kerala most of the time triggered by MJO only.
The West Indian Ocean or Arabian Sea Branch of SWM winds requires a trigger from MJO to make and onset. This has happened most of times in the past.

Whereas Bay branch just required CEW which will ensure monsoon onset over Andaman and North East Coast of India.

Lower level convergence max. is 40 and upper level divergence max. is 50 , and both are in line around the region of disturbance ….also as u said the shear lines are almost indicating the same point source outflows ….

subject of monsoon onset over kerala in response to sst over north indian ocean basin was studied by experts from NIOT, GOA… comparing there findings with tis year sst conditions, the conditions were very much similar to delayed onset

During ELNINO years by May end or June Arabian Sea will throw a system, as the MJO predominantly in Phase 8 or Phase 1 since east pacific is heating up. Since MJO predominantly in Phase 7 and 8, this will suppress moisture in Bay. This is why we are *not getting May cyclone in Bay of Bengal, rather forming in Arabian Sea.

When a monsoon season has more Kelvin or Rossby Waves, then monsoon in that season will fail. The upcoming SWM season also likely to see frequent Rossby and Kelvin Waves and MJO might not be frequent as it was in previous times.

The reason is ELNINO. this phenomenon suppresses moisture in Indian Ocean in the long run and the Pacific Ocean keeps MJO with itself for most of the time.

Kelvin Wave likely to help monsoon to some extent but the reflective of Rossby might not. This Rossby wave will help the Upper Level moisture to get developed, this will bring occassional thunder storms and suppresses the lower level moisture and the lower level steering winds will not get the required moisture for monsoonal rains.

This is when the Positive IOD will help the lower level winds to get moisture during SWM. This time we might get Positive IOD but not going to sustain and will be back to Neutral. The unsettled IOD during this season might fail the SWM 2015.

There is an advantage for Chennai. During ELNINO when there is no Positive IOD, then those years Chennai got Normal Rainfall during June to September, since upper level gets more active, by nature Chennai gets TS during this season, it helps Chennai to get normal rainfall during SWM season, this is due to failure of Positive IOD establishment.

Hence we will see more Rossby Wave and Less MJO this season.
Also IMD has pulled the right string and Chennai might get normal rainfall during SWM. This is just my assessment based on some logic, correct me if i am wrong.

Tamil Nadu will receive more than 32 per cent of its total annual rainfall from the South West Monsoon (SWM) (between June and September 2015) and this is despite lying in the rain shadow area to SWM, say researchers at the Agro Climate Research Centre, Tamil Nadu Agricultural University.

Districts such as Coimbatore, Erode, Karur, Theni, Tirupur and Madurai can expect near normal rainfall, while some of the Southern districts such as Ramanathapuram, Sivagangai, Tirunelveli, Thiruvarur, Tuticorin and Virudhunagar will receive below normal rainfall, the researchers say.

Researchers said that the forecast is based on the Southern Oscillation Index of summer season and sea surface temperature values of Pacific and Indian Oceans using Australian Rainman International V.4.2 software. The rainfall probability is said to be 60 per cent.

The Indian Meteorological Department (IMD) may have downgraded its monsoon outlook for the June-September season to 88 per cent, but it is premature to say this will be the same in the southern peninsula, Geetha Agnihotri, in-charge director, Indian Meteorological Department, Bengaluru, said.
According to earlier reports from IMD, the south west monsoon was supposed to hit the Kerala coast on May 30 and arrive in Coastal and other parts of Karnataka in five days. But now, the monsoon is likely to hit the Kerala coast on Friday.

If India’s monsoon forecast turns out to be accurate, the country will be facing its 12th worst drought since 1950 and two consecutive years of the calamity for only the fourth time and the first time in 30 years. However, a private weather service and the meteorological department’s own track record raise some questions on the forecast.

On Tuesday, the Earth System Science Organisation and the India Meteorological Department (IMD) downgraded the operational long-range forecast for the southwest monsoon (June-September) rainfall from its April figure of 93 per cent (with an error margin of five per cent) of the normal to 88 per cent (four per cent). The forecast thus shifted from a below-normal monsoon to a deficient one, which implies a drought.

This makes it the first forecast of a drought before the onset of the monsoon since the department began forecasts in 1988. However, even given the 10 per cent margin of error around pre-monsoon forecasts, the IMD got only three of the last eight monsoon forecasts right, underestimated two and overestimated three, an analysis by The Hindu shows.

Rs 500 crore corpus to fight price rise of essentials; government ready with contingency plan
The government is ready with a contingency plan to tackle the impact of deficient monsoon rains on the overall economy , agriculture minister Radha Mohan Singh said on Wednesday , saying that the Rs 500 crore corpus that government has created for price stabilization would be used for market intervention to moderate prices of onions, potatoes and even pulses.

All convergence and divergence shifted to Arabian Sea, also 700HPA vorticity so far were around SAP and NTN too shifting to Arabian Sea, whatever TS formed so far in SAP since morning was due to mid level ridge passing through 14N, it is still available, but might shift anytime.

The following pic shows the ridge, the ACC in Deep Blue and Light Blue is moisture phase. The border of Deep Blue and Light Blue is Ridge.

A new upper air trough at 4.5 km a.s.l has formed over Andaman. This trough is expected to breed our 2nd UAC! .Likely to be AP’s again, but coastal TN will get rains as long as westerlies prevail and SWM sets in fast.